Businesses and individuals rely heavily on e-mail systems to communicate. Because of the critical nature of these communications, it is essential that e-mail systems are both reliable and efficient. Current methods known in the art typically co-locate a message transport agent (MTA) and a message store within a single integrated system in order to manage delivery to users and for message transmission. This method may result in two single points of failure.
First, the message store may be a single point of failure. The message store contains all messages in the system. If the message store fails, the MTA cannot access the message store. A system failure will result because the MTA cannot deliver new incoming messages to the message store and no outgoing messages on the message store can be transmitted by MTA.
Second, the MTA may be a single point of failure. The MTA is responsible for delivering and transmitting messages to the message store. If the MTA fails, a system failure will result because no new incoming messages can be delivered to the message store and no new outgoing message may be transmitted from the message store.